Combustion apparatus



Oct. 7, 1930; K, A, MAYR 1,777,411

COMBUSTION APPARATUS 5 Sheets-Sheet 2 Filed Oct. 4, 1927 avwemtoz Oct.7, 1930. K, MAYR 1,777,411

COMBUST ION APPARATUS Filed Oct. 4, 1927 5 Sheets-Sheet 3 Patented On.7, 1930 1mm. A. MAYR, or NEW YORK, N. Y.,

AS SIGNOR TO SIEMENS-SCHUUKERT'WERKE AK- TIENGESELLSCHAFT. OFSIEMENSSTADT, N EAR BERLIN, GERMANY, A CORPORATION OF GERMANY COMBUSTIONAPPARATUS Application filed October 4, 1927. Serial No. 228,857.

This invention relates to improvements in furnaces for powdered, liquidor gaseous fuels and has for its principal objects'provisions of animproved furnace construction which will more efliciently mix finelydivided fuel with the air for combustion to the general end that a morehomogeneous, complete and better combustion may be. secured.

Other objects of the present invention reside in the provision of aconstruction which will permit free and independent expansion of anyparts of the apparatus which are subect to high and variable heat.

v -A further object of the present invention resides in the provision ofa construction which Wlll provide for cooling of varlousparts of theapparatus by the entering air and for thereby raising the incoming airtemperature.

A further object of the present invention resides in the provision of afurnace construction which will afford a relatively cool zone orantechamber at certain points near the point where the fuel enterswhereby high and excessive radiant heat efiects in certain parts of thiszone or antechamber are considerably minimized and also in the provisionof a further main combustion chamber in which the more intense andcomplete combustion takes place. f

Other objects of the present invention reside in the provision of novelmeans for directing the fuel and air into the ante and main combustionchambers to the general end that better operating results are securedwhich will be more fully pointed out hereinafter.

Further and more detailed objects of the present invention reside in theprovision of a construction which will protect the burner tips againstexcessive heat and which will also keep these tips cool.

a A further object of the present invention resides in the provision ofa construction which will secure an intimate mixture of fuel and air sothat combustion may be completed within a very small space.

' ing or revolving action of the Provision is made for setting. up awhirlurning mix-, ture so that all zonesof the combustion space by theresultant will act equally and whereby stratified com-- bustion isavolded, even if the introduction of fuel and air is not initially suchthat an equal loading over the combustion space is secured.

A further object of the present invention resides in the provision ofmeans for setting up further turbulance of the burning mixture in orderto make the mixture more intimate and in order to prevent excessiverotary mo tion which might cause a throwing out of the coarse or badlyatomized fuel particles towards the cooler walls of the combustionchamber.

A further object of the present invention resides in the provision of aconstruction which will be simple to assemble and disassemble and onewhich will afford ready accessibility to the various parts.

Further objects and advantages will be hereinafter more fully set forthin the accompanyingspecification, defined in the claims and shown in theaccompanying drawings, which show by way of illustration what I nowconsider to be the invention.

In the drawings Figure l is a transverse sectional view of my improvedfurnace.

Fig. 2 is a transverse sectional view taken on line 2-2 of Fig. 1 andlooking in the direction of the arrows. 4

Fig. 3 is a sectional transverse view taken on line 38 of Fig. 1 andlooking in the direction of the arrows.

Fig. 4 is a diagrammatic view 'showing the direction of the various fueland air jets and the paths of flow of the fuel air which combinationafford the desired action. l

Fig. 5 is a diagrammatic view showing the impinging action of the fuelstreams.

7 According to the present invention, provision is made in anantechamber for introducing the fuel in impinging streams which somewhatincline toward the main combustion chamber. Air is also directed towardsthe finely divided fuel in this zone in tangential and inclined streamsto set up an initial' revolving. action and in this primary zone furtherair is introduced centrally and I a perfect embodiment of 75 i radiallyor perpendicularly to the axis of the combustion chamber in order toprovide further combustion air about the outside of the burning mass andin order to introduce air streams directly into the burning mass toprovide further turbulence and a complete and homogeneous combustionthroughout the entire space. The efiect ofthe co-acting air streams issuch that while the revolving action of the burning mass is maintained,such action is not allowed to become excessive or reach such a pointthat badly atomized fuel will be thrown out of the burning mass towardsthe relatively cooler walls of the combustion chamber.

The construct-ion is such that a cloud of fuel particles is pierced bystreams of air and then the mixture of air and fuel is directed topierce flowing streams or a sheet of fresh air so that the burning fuelis con-- stantly being attacked by air as the combustion proceeds.

The general const-ruction and the manner in which combustion is securedwill be first explained and afterwards various features of design willbe set forth in further detail.

Broadly, the entering incoming air enters the apparatus from an upperjacket space generally designated 10 in Fig. 1. 11 and 12 are the fuelnozzles, two of these are shown inthe present embodiment, but it isapparent that any desired number may be used. These nozzles extendtowards one another and incline somewhat downwardly as shown in Figs. 1and 2. The antechamber 13 is defined by a refractory construction,generally designated 14 and provided with openings 15 for the burners 11and 12, which openings are suitably inclined. Other openings 16, Figs. 1and 2 are provided, which openings extend tangentially and downwardly toset up a whirling or revolving action of theburning fuel and alsoprovide air for supporting combustion in part. The top of theantechamber is provided with a central openin 17 which directs air forsup porting com ustion centrally into the burning mass. The pulverizedfinely divided fuel streams are suitably ignited. They impinge upon oneanother causing spreading and deflection of the fuel.

If two burners are employed the opening 17 is preferably oval in contouras shown in Figs. 2' and 5. If the burners were disposed horizontallyinstead of being inclined a flat disc-like body of fuel would resultfrom the impinging streams. The inclination of the burners causes aparabolic dispersion of the fuel particles spreading outwardly asindicated by lines 25? on Fig. 4. The oval permits a ready egress anddevelopment of this desired diverted fuel flow. The impinging center ofthis fuel mass is directly attacked by the air stream 27 and preventsundesired upward spreading of the fuel particles.

It is th'e'intention that the combustion be relatively slight in theprimary antechamber 13 and that the more intense and more completecombustion take'place in the main combustion chamber 18. As .the burningfuel mass passes downwardly from the antechamber 13 into the maincombustion chamber 18, this burning mass is attacked by further air 'forsupporting combustion, which enters through tangentially disposedopenings 19 in a lower refractory construction, generally designated 20.This air supply sets up a further and more intense whirling action ofthe burning mass, and creates a more intense combustion. The air forsupporting combustion is further augmented by additional air streamswhich" are introduced in a substantially radial direction into theburning mass through ports 21. The effect of the latter two air streams,viz the tangential streams and the radial streams is to cause an intenseand complete combustion in a comparatively short space in the combustionchamber 18 and the radial streams serve the further purpose of breakingup any stratification of combustion which might have occurred on accountof unequal supplies of fuel from the burners or une ual supplies of airfor combustion. The com ustion in the main combustion chamber ishomogeneous throughout and furthermore excessive whirling action isobviated which might cause throwing out of coarse or badly atomizedfuel'particles towards the walls 22 of the combustion chamber.

F ig. 4 shows in somewhat diagrammatic manner the stream action. Thelines 25 (see also Fig. 5) represent the entering fuel streams whichimpinge and form a cloud. Lines 26 represent the first or uppertangential air streams and lines 27 represent the central air streams.

In practice, approximately twenty per cent of the air may enter at 26and say forty per cent on the paths 27. Lower down, the lower tangentialair jets are represented by the lines 28 and the radial jets are reresented by lines 29. Combustion is extreme y intense'at' point lOO .quantity of cool fresh air which is drawn in directly from the outsideof the apparatus around the burners.

should occur in the antechamber. Ignition and initial combustionpreferably takes place in the center adjacent the division of the anteand main chambers and accordingly the antechamber is comparatively cool.The

incoming air-from casing 10 even though it may be initially somewhatpreheated serves to cool the refractory constructions 14 and20.

' Oonstructz'on details Provision is made for supporting refractoryconstructions 14 and 20 independently of each other from the top of thefurnace. As shown, the top part of the casing 10 comprises sheet metalplate structures 32, 33, 34 and 35. Plate 35 may be provided with anopening 36 opposite opening 17 and closed by a suitable heat resistinglid 37 which may be removed to provide access to the interior of thefurnace. The refractory construction 14 may be made in sectional form oras here shown it can be in a single piece. It is "preferably supportedby bolts-38 which are spring supported by means'such as 39 from plate35. Bolts 38 preferably are located in flange portions 40 upon the outerand cooler side of the refractory 14 so-as to becooled by the incomingair. The refractory section 14 may further be provided with exteriorcentering and aligning flanges 41 best shown in Fig. 2.

The refractory construction 20 is supported independently of therefractory section 14 and is preferably spaced slightly therefrom. Thelower refractory section 20 preferably but not necessarily, is made insections. In Fl%. 3 this refractory construction is shown as eing m'adeup of four sections designated 20, 20 20 and 20, but it willbehnderstood that any. number of sections may be employed. Each sectionis provided with integral radial flange portions 43. In order to supportthe refractory assembly 20, a num- 1 her of looped end spring hangerbolts 44 are provided which are carried by the plate section 33 andwhich support a ring 45. The ends of the flanges 43 project over andrest upon this ring. Other spring hangers 46 are provided which areresiliently supported by the plate member 33 and which have bolts 47carrying horizontally extending members 48 at their lower ends whichproject into apertures in the flange portions 43.

The foregoing construction provides for free expansion of the variousrefractory parts when highly heated. The springs in the hangers arepreferably of a material which does not readily lose its resiliencyunder high heat and these spring hangers hold the re-- effected in theantechamber.

fractory parts yieldingly to the upper plate any ordinary refractorymaterial but on account of the high and intense radiant heat in the maincombustion chamber, the refractory 20 should be built of high heatresisting material, for instance, carborundum, nickel chromium or thelike. The highly heated refractory 20 is cooled by the incoming airwhich not only cools the ribs 43, but also cools the main body inpassing the admission channels.

It will be understood that the mixing of some air and dispersion of fuelparticles and the setting up of an initial whirling action is The fuelair mixture is directed toward the main combustion chamber by theinclination of the fuel streams and by the direction of the air streams26'and 27. The stream 27 directly attacks the point of impingement ofthe fuel streams and supplies air at this point forming in eifect an aircore for the fuel air mixture. This mixture also has an air envelopeprovided by stream 26.

Subsequently in the main combustion chamber, the balance of the air issupplied for effecting the more complete and intense combustion. Thetangential streams 28 act to supplement the whirling action and aflordan air envelope for the burning-mass. Ultimately the whirling action isbroken up by the radial streams 29 which cause extreme turbulence andvery rapid and intense burning. Intense radiation and high heatconditions are maintained in the main combustion chamber and relativelycooler conditions are main tained in the antechamber. All parts subjectto heat are adapted for expansion independently of the other parts andatthe same time these parts are kept in place by the hanger constructionspacers and like parts which are employed. The expansion.of the variousparts furthermore does ing streams therein, means for directing airstreams toward the the fuel, and means point of impingement of forfurther directing air tangentially with respect to the chamber and uponthe aforesaid fuel to cause a revolving v action thereof.

3. The invention set forth in claim 1, in

which means is provided for inclining the fuel streams which impinge insaid chamber.

4. A combustion apparatus including in combination, a mixing chamber anda combustion chamber, means for directing a fuel air mixture in adiverging and. rotatably whirling manner from the mixing chamber intothe combustion chamber, and means for attacking the said mixture afterits entry into and while it burns in the combustion chamber byadditional air streams.

5. The invention set forth in claim 4, in which means isprovided fordirecting the attacking air streams tangentially and radially withrespect to the mixing chamber to cause whirling and turbulence.

6. A combustion furnace including a combustion chamber, means forinitially mixing fuel and air for supply to said chamber, said meanscomprising means for causing-a revolving action of the fuel and airmixture entering the chamber, and means comprising parts which areradially disposed with respect to the main axis of flame propagation ofthe burning mixture for breaking up said revolving action by further airsupply.

7. A combustion apparatus including achamber into which a fuel mass isintroduced,

- means for directing air centrally in said of said streams toward themain combustion troducing chamber to provide an air core for the fuelmass, and means for directing air about the outside of said fuel mass ina tangential di- 'rection with respect to the combustion chamber to setup a whirling action of the fuel mass therein.

8. A combustion apparatus including a main combustion chamber havingenclosing wall portions, means adjacent the combustion chamber fordirecting fuel in impinging streams and for inclining the directionchamber, means for conducting an air stream through the wall portionsand at points adjacent the aforesaid means to cool the wall portions,and means for directing an air stream toward the point of impingent andtoward the main combustion chamber.

9. The invention set forth in claim 2 in point of introduction of thefuel, and means for causing turbulence by introducing supplemental airstreams thereinto.

11. A combustion furnace having in combination, a combustion chamber inwhich fuel mixture burns, means for introducing air to the combustionchamber in a direction which is substantially tangential to the mass ofburning mixture to cause a whirlingaction of said mixture, and means fordirecting additional air to support combustion into said chamber, saidmeans directingsaid last mentioned air in a direction generallyperpendicular to the tangential air streams and in a direction co-axialwith the main axis of flame propagation of the burning mixture.

12. A combustion furnace having a chamber, means for forming therein afuel air mixture including air supplying means for supplying air to theoutside of a fuel cloud inside the chamber and air supplying means forsupplying air to the center of said cloud, means for supplying furtherair to the mixture after it has commencedto burn, said means comprisingair supplying means for admitting air in a direction to create awhirling action of the burning mass and also including air supplyingmeans for admitting additional air to breakup the whirling action.

13. A combustion apparatus including a chamber into which fuel isintroduced, means for directing air centrally into said chamber toprovide an air core for the fuel means,tand means for introducing airtangentially with respect to and into said chamber to set up a whirlingaction therein.

.In testimony whereof I hereto aifix my signature.

KARL A. MAYR.

which the fuel introducing means'is inclined also control the maindirection of-dispersion of the fuel in said chamber.

10. A combustion furnace having in com- M bination, a main combustionchamber in which combustion of burning mixture takes place, fuelintroducing means for introducing fuel into said chamber, means disposedin said chamber at a point beyond the point where the fuel is introducedtherein for inair substantially tangentially thereinto and with respectto the burning mass of fuel to cause a revolvin the burning mixture atpoints yond the action of

